JP2009080271A - Developer conveying device and image forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a developer conveying device that conveys developer smoothly by suppressing flocculation of the developer on a carrying body at a developer takeout part, and an image forming device. <P>SOLUTION: The image forming device includes: an image holding body (photoreceptor drum 3) configured to hold an image formed by a developer; a developer case (cartridge case 71) configured to accommodate the developer (toner T) and to have a supplying port 71A opening at a position facing the image holding body; a developer conveying body (toner carrying body 73) configured to carry the developer accommodated in the developer case toward the image holding body by generating a traveling electric field through a plurality of carrying electrodes; a vibrator 74 that vibrates the developer conveying body; and a vibrating region moving means (moving device 75 and controller 8) configured to move a vibrating region vibrated by the vibrator 74 along the developer conveying body in accordance with an amount of the developer in the developer case. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a developer conveying device and an image forming apparatus that convey a developer using a traveling wave electric field.

  In general, a developer transport device that transports a developer using a traveling wave electric field has a transport body in which a large number of linear transport electrodes are arranged in a line, and each transport electrode of the transport body is provided with each transport electrode. On the other hand, a traveling wave electric field is formed by sequentially applying a multiphase AC voltage, and the charged developer is conveyed. In such a developer transport apparatus, there is a problem that the developer aggregates on the transport body and the developer cannot be transported smoothly.

  In order to deal with such a problem, a developer conveying device having a vibrating body fixed at a predetermined position is known in order to apply vibration to a predetermined position of the conveying body (see Patent Document 1). According to this developer transport device, the developer aggregated on the transport body can be broken by shaking the entire transport body by applying vibration to a predetermined portion of the transport body by the vibration body.

JP 61-73167 A

  By the way, when the transport body is disposed obliquely so as to transport the developer stored in the case obliquely upward, a portion of the developer accumulated in the case is located on the upper surface side and is located in the vicinity of the transport body (Hereinafter, also referred to as a developer take-out portion) are sequentially conveyed by the conveyance body. In such a case, there is a problem that the developer cannot be smoothly transported when the developer aggregates on the transport body in the developer take-out portion.

  However, in the above-described prior art, since the vibrating body is fixed at a predetermined position, the position of the upper surface of the developer changes according to the amount of the developer in the case, and the developer take-out portion moves away from the vibrating body. In addition, since the vibration due to the vibrating body becomes difficult to be transmitted to the developer take-out portion, the developer may be aggregated on the transport body in the developer take-out portion and the above-described problem may occur.

  Accordingly, an object of the present invention is to provide a developer transport device and an image forming apparatus that can smoothly transport a developer by suppressing aggregation of the developer on the transport body in the developer take-out portion. And

  In order to solve the above problems, an image forming apparatus according to the present invention includes an image carrier that carries a developer image, and a developer that contains a developer and has a supply port that opens at a position facing the image carrier. A developer case that includes a developer case and a plurality of transport electrodes, and forms a traveling-wave electric field with the transport electrodes to transport the developer contained in the developer case toward the image carrier. A vibrating body that vibrates the developer conveying body, and a vibration region that is vibrated by the vibrating body is moved along the developer conveying body in accordance with the amount of the developer in the developer case. And a vibration area moving means.

  According to the present invention, since the vibration area on the transport body can be moved by the vibration area moving means, for example, the vibration area is moved so as to match the developer take-out portion that moves according to the amount of the developer. Thus, it is possible to suppress the developer from aggregating on the conveyance body in the developer take-out portion.

  The developer transport device according to the present invention includes a developer case that contains a developer and has a supply port that opens at a position facing a predetermined supply target, and a plurality of transport electrodes. Forming a traveling-wave electric field at a developer carrier that conveys the developer contained in the developer case toward the supply target, a vibrator that vibrates the developer carrier, and And a moving device that moves the vibrating body along the developer transport body.

  According to this, for example, by the control device of the image forming apparatus to which the developer conveying device is mounted, the vibrating body is moved by the moving device so as to fit the developer taking-out portion that moves according to the amount of the developer. Further, the developer can be prevented from aggregating on the conveyance body in the developer take-out portion.

  The developer transport device according to the present invention includes a developer case that contains a developer and has a supply port that opens at a position facing a predetermined supply target, and a plurality of transport electrodes. By forming a traveling-wave electric field, the developer transport body that transports the developer contained in the developer case toward the supply target, and the developer transport body are vibrated, and the developer transport is performed. And a plurality of vibrating bodies arranged along the body.

  According to this, for example, the control unit of the image forming apparatus to which the developer conveying device is mounted drives the vibrating body at a position corresponding to the developer take-out portion that moves according to the amount of the developer, thereby developing the image. It is possible to prevent the developer from aggregating on the conveyance body in the agent take-out portion.

  According to the present invention, it is possible to suppress the aggregation of the developer on the developer transport body in the developer take-out portion, so that the developer can be transported smoothly.

[First Embodiment]
Next, a first embodiment of the present invention will be described in detail with reference to the drawings as appropriate. In the drawings to be referred to, FIG. 1 is a side view showing a schematic configuration of a laser printer according to a first embodiment of the present invention, and FIG. 2 is a sectional view showing a structure of a toner supply device. FIG. 3 is a plan view (a) and a cross-sectional view (b) showing the toner carrier, and FIG. 4 is a diagram showing a waveform of a voltage output from each power feeding unit. 5 is a front view (a) and a cross-sectional view (b) showing the vibrating body. FIG. 6 is a cross-sectional view showing the toner conveyance state, a cross-sectional view (a) showing the state at time t1, a cross-sectional view (b) showing the state at time t2, and a time t3. It is sectional drawing (c) which shows the state of time.

<Laser printer>
As shown in FIG. 1, a laser printer 1 as an example of an image forming apparatus includes a paper transport mechanism 2, a photosensitive drum 3 as an example of an image carrier and a supply target, a charger 4, and a scanner unit 5. A toner supply device 7 as an example of a developer conveying device and a control device 8 are provided. Although not shown, the laser printer 1 is appropriately provided with known configurations such as a paper feed tray and a fixing device.

  The paper transport mechanism 2 is a known mechanism that transports the paper P from the paper feed tray, and transports the paper P to the transfer position of the photosensitive drum 3 via a plurality of rollers (for example, registration rollers 21).

  The photosensitive drum 3, the charger 4 and the scanner unit 5 have a known configuration. In brief, the surface of the photosensitive drum 3 is uniformly negatively charged by the charger 4 and then exposed by high-speed scanning of the laser beam LB from the scanner unit 5. As a result, the potential of the exposed portion changes and an electrostatic latent image based on the image data is formed. Next, toner T (see FIG. 2) as an example of a developer is supplied from the toner supply device 7 to the electrostatic latent image on the photosensitive drum 3, and this toner T is selectively applied on the surface of the photosensitive drum 3. By being carried on the toner image, a toner image is formed. Thereafter, the photosensitive drum 3 and the transfer roller 22 are rotationally driven so as to sandwich and convey the paper P between them, and the toner image carried on the surface of the photosensitive drum 3 at this time is transferred to the transfer roller 22. Is transferred onto the paper P.

<Toner supply device>
As shown in FIG. 2, the toner supply device 7 includes a cartridge case 71 as an example of a developer case, an agitator 72, a toner transport body 73, a vibrating body 74, and a moving device 75.

  The cartridge case 71 is formed of a member having relatively high rigidity such as resin, and a part of the wall thereof is constituted by a toner transport body 73. A supply port 71 </ b> A is formed above the cartridge case 71 so as to open at a position facing the photosensitive drum 3. The bottom of the cartridge case 71 contains a negatively chargeable, non-magnetic one-component black toner T mainly composed of polyester.

  The agitator 72 is rotatably provided at the deepest part in the cartridge case 71 and agitates the toner T accumulated in the cartridge case 71. The agitated toner T is negatively charged due to friction between the toners T and friction between the toner T and the toner transport body 73.

  As shown in FIG. 3B, the toner transport body 73 includes a support plate 731 that is a thin plate member made of synthetic resin, a plurality of transport electrodes 732 disposed on the support plate 731, and a support plate 731. And a coating film 733 covering the side where the transport electrode 732 is disposed. Here, as the coating film 733, for example, a nylon coating film which is a synthetic resin can be employed. The surface of the coating film 733 serves as a transport surface TS for transporting the toner T. Note that the toner conveyance body 73 formed in such a thin plate shape has lower rigidity than the cartridge case 71 and is likely to vibrate.

  As shown in FIG. 3A, the transport electrodes 732 are linear wiring patterns made of a metal thin film, and are arranged at equal intervals in the toner T transport direction and orthogonal to the toner T transport direction. They extend along the direction (the axial direction of the photosensitive drum 3) and are arranged in parallel to each other. As shown in FIG. 3B, the first feeding unit VA, the second feeding unit VB, the third feeding unit VC, and the fourth feeding unit VD that output voltages having different phases to the transport electrodes 732, respectively. Are appropriately connected. Specifically, the first power feeding unit VA, the second power feeding unit VB, the third power feeding unit VC, and the fourth power feeding unit VD are repeatedly connected to the respective transport electrodes 732 in this order from the upstream side in the transport direction. . In other words, every three transport electrodes 732 are connected to the same power supply unit (for example, the first power supply unit VA) every third. In the following description, for the sake of convenience, the transport electrode 732 connected to the first power supply unit VA is referred to as “transport electrode EA”, the transport electrode 732 connected to the second power supply unit VB is referred to as “transport electrode EB”, and third. The transport electrode 732 connected to the power supply unit VC is also referred to as “transport electrode EC”, and the transport electrode 732 connected to the fourth power supply unit VD is also referred to as “transport electrode ED”.

  Each of the power supply units VA to VD outputs a voltage having a waveform as shown in FIG. 4 by being appropriately controlled by the control device 8 disposed in the laser printer 1. In other words, the voltages output from the power supply units VA to VD have the same waveform, but are out of phase by 90 °. Specifically, the phase of the voltage waveform is delayed by 90 ° in the order of the first power supply unit VA, the second power supply unit VB, the third power supply unit VC, and the fourth power supply unit VD. Then, a traveling-wave voltage is applied to each transport electrode 732 by each of the power supply units VA to VD controlled by the control device 8 in this manner, thereby forming a traveling-wave electric field on the transport surface TS. .

  Specifically, at time t1 in FIG. 4, when “−550V” is negative and “−450V” is positive with respect to the intermediate potential “−500V”, the first power supply unit VA and the fourth power supply unit VD A negative voltage is output, and positive voltages are output from the second power supply unit VB and the third power supply unit VC. As a result, as shown in FIG. 6A, an electric field EF1 opposite to the transport direction is formed between the negative transport electrode EA and the positive transport electrode EB, and the positive transport electrode EC and the negative transport electrode EC are negative. An electric field EF2 is formed in the transport direction between the transport electrode ED. Therefore, a large amount of negative toner T is collected around the positive transport electrodes EB and EC. A small amount of toner T that could not move to the positive transport electrodes EB and EC remains between the negative transport electrodes ED and EA.

  As shown in FIG. 4, at time t2, a negative voltage is output from the first power supply unit VA and the second power supply unit VB, and a positive voltage is output from the third power supply unit VC and the fourth power supply unit VD. . As a result, as shown in FIG. 6B, an electric field EF1 is formed between the negative transport electrode EB and the positive transport electrode EC, so that the toner around the transport electrodes EB and EC at time t1. T moves around the transport electrodes EC and ED that have become positive this time. At this time, a small amount of toner T between the transport electrodes ED and EA also moves around the transport electrodes EC and ED. Similarly, at time t3 (see FIG. 4), as shown in FIG. 6C, an electric field EF1 is formed between the negative transport electrode EC and the positive transport electrode ED, so that time t2 The toner T around the transport electrodes EC and ED moves around the transport electrodes ED and EA that have become positive this time. By repeating the above operation, the toner T is transported on the transport surface TS.

  As shown in FIG. 2, the toner conveyance body 73 configured as described above constitutes a cylindrical first toner conveyance body 73 </ b> A disposed in the cartridge case 71 and a part of the wall of the cartridge case 71. And a curved second plate-shaped toner conveying body 73B. Specifically, the second toner conveyance body 73B is formed along the inclined portion B1 inclined obliquely upward from the bottom of the cartridge case 71 and the first toner conveyance body 73A, and supplied at the upper edge thereof. And a cylindrical part B2 constituting a part of the mouth 71A. In the toner transport body 73 configured as described above, the toner T collected at the bottom of the cartridge case 71 is transported obliquely upward by the inclined portion B1 of the second toner transport body 73B, and then the second toner transport body. By being conveyed between the cylindrical portion B2 of 73B and the first toner conveyance body 73A, it is conveyed toward the photosensitive drum 3.

  When the electrostatic latent image is formed on the photosensitive drum 3, the toner T that has moved to the vicinity of the supply port 71 </ b> A moves to the photosensitive drum 3 so as to be attracted to the electrostatic latent image. When no electrostatic latent image is formed on the photoconductive drum 3, the toner T passes through the photoconductive drum 3, and the first toner transport is performed until the application of voltage to the first toner transport body 73A is completed. It continues to be conveyed on the body 73A.

  As shown in FIG. 5A, the vibrating body 74 includes a long beam-like member 74A that is slidably contacted with the toner conveying body 73, a coil 74B that is fixed to the center of the beam-like member 74A, and a coil And a core 74C that vibrates 74B in the axial direction.

  As shown in FIGS. 5A and 2, the beam-shaped member 74 </ b> A is a rectangular member extending in parallel to the transport electrode 732, and is configured by a member having higher rigidity than the toner transport body 73. The length of the beam-like member 74A can be arbitrarily set, but is preferably formed to be longer than the length of the transport electrode 732 in the longitudinal direction. According to this, when the toner T aggregates on the transport electrode 732, the aggregated toner T can be favorably broken.

  As shown in FIG. 5B, one end of the coil 74B is fixed to the beam-like member 74A, and the other end is arranged in the core 74C. The coil 74 </ b> B is supplied with an alternating voltage from the control device 8, so that a voltage having the same magnitude that is opposite in polarity is applied alternately. For this reason, a magnetic field whose polarity is reversed is alternately generated from the coil 74B. A current sensor AS for detecting a current flowing through the coil 74B is provided between the coil 74B and the control device 8, and a signal detected by the current sensor AS is output to the control device 8. The Here, the coil 74B and the current sensor AS correspond to an example of a detection unit. That is, when the amount of movement of the coil 74B changes due to a change in the load applied to the coil 74B that vibrates with respect to the core 74C, the current flowing through the coil 74B changes, and this current is detected by the current sensor AS.

  In the present embodiment, the load applied to the coil 74B varies according to the amount of toner T accommodated in the cartridge case 71 as shown in FIG. Specifically, when the toner T accumulates up to the same position as the vibrating body 74 in the toner transport body 73, the load applied to the coil 74B increases, and the upper surface of the toner T is located below the position of the vibrating body 74. When the TF is located, the load applied to the coil 74B is reduced. When the load applied to the coil 74B increases, the current flowing through the coil 74B increases. When the load applied to the coil 74B decreases, the current flowing through the coil 74B decreases. Thereby, the position of the upper surface TF of the toner T can be estimated by the control device 8 by detecting the current flowing through the coil 74B.

  As shown in FIG. 5B, the core 74C includes a bottomed cylindrical outer core portion C1, an inner core portion C2 disposed within the outer core portion C1 with a predetermined gap (gap), and an outer side. A permanent magnet portion C3 is provided between the bottom surface of the core portion C1 and the inner core portion C2. And in the core 74C comprised in this way, a magnetic field generate | occur | produces from the gap. Therefore, when an AC voltage is applied, the coil 74B disposed in the magnetic field receives a force alternately in the axial direction according to Fleming's law and vibrates with respect to the core 74C.

  As shown in FIG. 2, the moving device 75 supports the core 74 </ b> C of the vibrating body 74, and in detail, in the toner T conveying direction, the vibrating body 74 extends along the inclined portion B <b> 1 of the second toner conveying body 73 </ b> B. It is moved along. As the moving device 75, for example, a device provided with rails, wheels, and a motor, a device provided with a rack, a pinion, and a motor can be adopted. Here, the moving device 75 and a control device 8 to be described later correspond to an example of a vibration area moving means.

<Control device 8>
Next, the control device 8 will be described. In the drawings to be referred to, FIG. 7 is a flowchart showing the operation of the control device.

  The control device 8 includes a CPU, a RAM, a ROM, and the like, and appropriately controls the AC voltage supplied to the drive of each part of the laser printer 1 and the toner conveyance body 73, as well as the current sensor AS (see FIG. 5B). The position of the vibrating body 74 is controlled according to the amount of the toner T by controlling the moving device 75 based on the signal from. Specifically, the control device 8 performs control according to the flowchart shown in FIG. Here, the initial position of the vibrating body 74 can be arbitrarily set, and when performing control for lowering the vibrating body 74 as in the present embodiment, the toner T in a state where the toner T is accommodated to the maximum extent. A position corresponding to the upper surface TF of the above or a position above this position may be set as the initial position.

  As shown in FIG. 7, when receiving a print instruction from the user (START), the control device 8 first applies an AC voltage to the vibrating body 74 to vibrate the vibrating body 74 (S1). Here, the “print instruction” is a signal input to the control device 8 by an operation of an operation panel provided on the outer surface of the laser printer 1 or a computer connected to the laser printer 1, and printing of the paper P Information such as the number of copies is included. After step S1, the control device 8 determines whether or not the current value is less than a predetermined value based on the signal from the current sensor AS, so that the vibrating body 74 corresponds to the position corresponding to the upper surface of the toner T ( In the following, it is determined whether or not it is separated from the “toner upper surface position” (S2).

  If it is determined in step S2 that the current value is less than the predetermined value (away from the toner upper surface position) (Yes), the control device 8 controls the moving device 75 to move the vibrating body 74 diagonally downward by a predetermined amount. (S3). After step S3, the control device 8 determines whether or not the vibrating body 74 is positioned at the toner upper surface position by determining whether or not the current value has become equal to or greater than a predetermined value (S4).

  If it is determined in step S4 that the current value is not equal to or greater than the predetermined value (not positioned at the toner upper surface position) (No), the control device 8 returns to step 3 and again places the vibrating body 74 diagonally downward. Is moved by a predetermined amount. When it is determined in step S4 that the current value has become equal to or greater than the predetermined value (positioned on the toner upper surface position) (Yes), the control device 8 executes printing (S5). Note that if the control device 8 determines that the current value is not less than the predetermined value (positioned at the toner upper surface position) in Step S2 (No), the process proceeds to Step S5.

  After step S5, the control device 8 determines whether printing for the number of prints corresponding to the print instruction has been completed based on the print instruction information (S6). If it is determined in step S6 that printing has not been completed (No), the control device 8 returns to the process of step S2 and again determines whether or not the vibrator 74 is separated from the toner upper surface position. If it is determined in step S6 that printing has been completed (Yes), the control device 8 stops the application of the AC voltage to the vibrating body 74 and stops the vibration of the vibrating body 74 (S7). The operation by is terminated.

  Next, the operation of the toner supply device 7 controlled by the control device 8 will be described. In the drawings to be referred to, FIG. 8 is a cross-sectional view (a) showing a state where the vibrating body is located at the toner upper surface position, and a cross-sectional view showing a state where the upper surface of the toner is lowered from the state shown in FIG. FIG. 5B is a cross-sectional view illustrating a state where the vibrating body moves to the toner upper surface position.

  As shown in FIG. 8A, for example, when a printing instruction is input to the control device 8, if the vibrating body 74 is positioned at the toner upper surface position, the control device 8 causes the above-described steps S1 to S2. The process of No → S5 is executed. As a result, the vibration member 74 vibrates and a portion TT at which the toner T starts to be conveyed by the toner conveyance body 73 (hereinafter, also referred to as “toner extraction portion TT”) is favorably collapsed. The printing is executed after being transported satisfactorily by the body 73.

  Then, the control device 8 repeats the processes in steps S2 to S6 described above until printing for the number of prints instructed by the print instruction is completed. During such processing, when the toner T is consumed by printing and the upper surface position of the toner is lowered as shown in FIG. 8B, the load applied to the vibrating body 74 is reduced and flows to the vibrating body 74. The current becomes smaller. When the current value becomes less than the predetermined value, the control device 8 determines Yes in step S2, and executes the processes of steps S3 and S4. As a result, as shown in FIG. 8C, the vibrating body 74 moves to the toner upper surface position. Then, after the vibrating body 74 reaches the upper surface position of the toner, the control device 8 executes the process of step S4; Yes → S5 described above, so that the toner take-out portion TT is surely broken and the toner T The conveyance is executed well.

According to the above, the following effects can be obtained in the present embodiment.
By causing the vibrating body 74 to move following the toner extraction portion TT, aggregation of the toner T on the toner conveyance body 73 in the toner extraction portion TT can be suppressed, so that the toner T can be smoothly conveyed. it can.

  Since the position of the upper surface of the toner can be accurately detected by the coil 74B and the current sensor AS, the vibrating body 74 can be reliably positioned at the toner extraction portion TT. In addition, since the coil 74B, which is a component of the vibrating body 74, is also used as a sensor for detecting the upper surface position of the toner, the components can be shared and the cost can be reduced.

  Since the second toner conveyance body 73B to be vibrated by the vibrating body 74 constitutes a part of the cartridge case 71, the vibrating body 74 can be disposed outside the cartridge case 71 and can be moved well. it can.

[Second Embodiment]
Next, a second embodiment of the present invention will be described in detail with reference to the drawings as appropriate. Note that, in the present embodiment, a part of the structure of the toner supply device 7 according to the first embodiment is changed, and therefore, the same reference numerals are given to the same components as those in the first embodiment. The description thereof will be omitted. In the drawings to be referred to, FIG. 9 is a cross-sectional view showing the structure of the toner supply device according to the second embodiment, and FIG. 10 is a flowchart showing the operation of the control device according to the second embodiment.

  As shown in FIG. 9, unlike the first embodiment, the toner supply device 7 ′ according to the second embodiment employs a plurality of vibrating bodies 74 and a control device 8 ′ as an example of a vibration area moving unit. As an example of the detection means, a mechanical upper surface position detection sensor 9 is employed.

  The plurality of vibrating bodies 74 are arranged at predetermined intervals from each other along the inclined portion B1 of the second toner transport body 73B, specifically along the transport direction of the toner T.

  The upper surface position detection sensor 9 includes a float 91 placed on the upper surface TF of the toner T, and a swing arm that rotatably supports the float 91 at one end and is rotatably supported by the cartridge case 71 at the other end. 92 and an angle sensor 93 for detecting the angle of the swing arm 92. The signal detected by the upper surface position detection sensor 9 (angle sensor 93) is output to the control device 8 '.

  The control device 8 ′ calculates the amount of toner T based on the signal from the upper surface position detection sensor 9, and selectively outputs a signal to the plurality of vibrating bodies 74 according to the calculated amount of toner T. Thus, it has a function of vibrating the vibrating body 74 located at the toner upper surface position. That is, the control device 8 ′ moves the vibration region vibrated by the vibrating body 74 along the toner transport body 73 by selectively vibrating a predetermined vibrating body 74 from among the plurality of vibrating bodies 74. Specifically, the control device 8 'performs control according to the flowchart shown in FIG.

  As shown in FIG. 10, when receiving a print instruction from the user (START), the control device 8 'first calculates the amount of toner T based on a signal from the upper surface position detection sensor 9 (S11). After step S11, the control device 8 'selects the vibrating body 74 located at the toner upper surface position from the plurality of vibrating bodies 74 according to the calculated toner amount (S12). Here, the relationship between the toner amount and the vibration body 74 to be selected may be created as a map by conducting experiments or simulations in advance. Note that the number of vibrating bodies 74 to be selected may be any number.

  After step S12, the control device 8 'applies an AC voltage to the vibrating body 74 to vibrate the vibrating body 74 (S13), and then executes printing (S14). After step S14, the control device 8 'determines whether printing for the number of prints corresponding to the print instruction has been completed based on the print instruction information (S15). If it is determined in step S15 that printing has not been completed (No), the control device 8 'returns to the process of step S11. If it is determined in step S15 that printing has been completed (Yes), the control device 8 ′ stops applying the AC voltage to the vibrating body 74 and stops the vibration of the vibrating body 74 (S16). The operation by is terminated.

According to the above, in addition to the same effects as those of the first embodiment, the following effects can be obtained in the second embodiment.
Unlike the first embodiment, it is not necessary for the vibrating body 74 to be in sliding contact with the toner transport body 73, so that the wear of the toner transport body 73 can be suppressed.
Moreover, generation | occurrence | production of noise can be reduced by selecting and vibrating a part of vibrating body 74. FIG.

The present invention is not limited to the above embodiments, and can be used in various forms as exemplified below.
In the first embodiment, only the vibrating body 74 is slidably brought into contact with the toner transport body 73, but the present invention is not limited to this. For example, as shown in FIG. The vibration suppressing member 76 may be brought into sliding contact with the toner conveyance body 73. Specifically, the vibration suppressing member 76 is positioned on the front side in the moving direction of the vibrating body 74 and is in contact with the toner conveying body 73. The vibration suppressing member 76 is positioned on the rear side in the moving direction of the vibrating body 74. A rear-side vibration suppressing portion 76B that comes into contact with the carrier 73 and a bottom wall portion 76C that connects these vibration-suppressing portions 76A and 76B are provided. According to this, it is possible to suppress the propagation of the vibration to the outside of the front vibration suppressing portion 76A and the rear vibration suppressing portion 76B, and the vibration condition of the toner conveying body 73 between these vibration suppressing portions 76A and 76B is set as the vibration body. Regardless of the position 74, it can always be the same, so the upper surface position of the toner can be detected more accurately. The vibration suppressing member 76 may be formed integrally with the core 74C of the vibrating body 74. Further, the material of the vibration suppressing member 76 is arbitrary, but a material having higher rigidity than that of the toner conveying body 73 is desirable, and the larger the mass, the better.

  In the first embodiment, the current sensor AS is adopted as one component of the detection means, but the present invention is not limited to this, and may be a voltage sensor, for example. In this case, the AC bias supplied from the control device 8 to the coil 74B may be subjected to constant current control. According to this, since the voltage applied to the coil 74B changes according to the change in the load applied to the coil 74B, the toner upper surface position can be detected as in the above-described embodiment. Further, the current sensor and the voltage sensor may be built in the control device 8. Further, in each of the above-described embodiments, any detection means may be employed, for example, an optical sensor may be employed.

In the first embodiment, the core 74C is fixed to the main body side (specifically, the moving device 75) of the laser printer 1 and the coil 74B is vibrated. However, the present invention is not limited to this, and the coil 74B is disposed on the main body side. The core 74C may be vibrated by being fixed.
In the first embodiment, the vibrating body 74 is constantly vibrated during printing. However, the present invention is not limited to this, and the vibration of the vibrating body 74 may be stopped during printing. In this case, for example, it can be realized by appropriately modifying the flowchart of FIG. 7 to obtain a flowchart as shown in FIG. Specifically, as shown in FIG. 12, the vibration stop process (S7) in the flowchart of FIG. 7 is moved before the print execution process (S5), and when it is determined No in step S6, What is necessary is just to comprise so that it may return to S1.

  In the first embodiment, the vibrating body 74 moves only diagonally downward. However, the present invention is not limited to this, and the vibrating body 74 may be moved diagonally upward. Specifically, for example, a sensor that detects the replenishment of the toner T may be provided, and the vibrating body 74 may be moved obliquely upward to the uppermost position based on the output value from the sensor.

  In each of the embodiments described above, the vibration region to be vibrated by the vibrating body 74 is set in the toner extraction portion TT, but the present invention is not limited to this. For example, even when the toner T is vibrated at a position away from the toner removal portion TT by a predetermined distance, if the toner T of the toner removal portion TT can be satisfactorily broken, the toner removal portion TT is moved away from the toner removal portion TT by a predetermined distance. The vibration region may be moved so that it is always located.

In each of the above-described embodiments, the photosensitive drum 3 is used as a supply target. However, the present invention is not limited to this, and may be, for example, a developing roller.
In each of the above-described embodiments, the vibration body including the coil 74B, the core 74C, and the like is employed. However, the present invention is not limited to this, and may be, for example, a piezo element.

  In each of the above embodiments, the toner upper surface position is estimated based on the signal from the detection unit. However, the present invention is not limited to this. For example, the remaining amount of toner is estimated from the number of printed sheets, and The upper surface position of the toner may be estimated from the remaining amount. Further, the upper surface position of the toner may be estimated by an optical method. That is, for example, the light upper surface position may be estimated based on the amount of light that changes according to the amount of toner by receiving light emitted from the light emitting portion of the optical sensor along the upper surface of the toner at the light receiving portion. .

In each of the above embodiments, the second toner conveyance body 73B that is vibrated by the vibration body 74 is configured as a part of the cartridge case 71. However, the present invention is not limited to this and may be disposed in the cartridge case.
In each of the above embodiments, the vibrating body 74 is moved or the plurality of vibrating bodies 74 are arranged along the toner T conveyance direction, but the present invention is not limited to this. For example, the vibrating body 74 may be moved or a plurality of vibrating bodies 74 may be arranged in a direction oblique to the toner T conveyance direction.

In each of the above embodiments, the present invention is applied to the laser printer 1, but the present invention is not limited to this, and the present invention may be applied to other image forming apparatuses such as a copying machine and a multifunction machine.
In each of the above embodiments, the photosensitive drum 3 is employed as the image carrier, but the present invention is not limited to this, and for example, a belt-shaped photosensitive member may be employed.
In the above embodiment, the toner T that is negatively charged is employed. However, the present invention is not limited to this, and a toner that is charged positively may be employed. In this case, the charged state of the photosensitive drum or the like may be reversed from that in the above embodiment.

1 is a side view showing a schematic configuration of a laser printer according to a first embodiment of the present invention. FIG. 3 is a cross-sectional view illustrating a structure of a toner supply device. FIG. 4 is a plan view (a) and a cross-sectional view (b) showing a toner transport body. It is a figure which shows the waveform of the voltage output from each electric power feeding part. It is the front view (a) which shows a vibrating body, and sectional drawing (b). FIG. 4 is a cross-sectional view showing a toner conveyance state, a cross-sectional view (a) showing a state at time t1, a cross-sectional view (b) showing a state at time t2, and a cross-section showing a state at time t3. It is a figure (c). It is a flowchart which shows operation | movement of a control apparatus. A cross-sectional view (a) showing a state where the vibrating body is located at the toner upper surface position, a cross-sectional view (b) showing a state where the upper surface of the toner is lowered from the state shown in FIG. It is sectional drawing (c) which shows the state which a body moves. FIG. 6 is a cross-sectional view illustrating a structure of a toner supply device according to a second embodiment. It is a flowchart which shows operation | movement of the control apparatus which concerns on 2nd Embodiment. It is sectional drawing which shows the form which provided the vibration suppression member in the vibrating body. It is a flowchart which shows the other control method by the control apparatus which concerns on 1st Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Laser printer 3 Photosensitive drum 7 Toner supply apparatus 8 Control apparatus 71 Cartridge case 71A Supply port 73 Toner conveyance body 73A 1st toner conveyance body 73B 2nd toner conveyance body 74 Vibration body 74A Beam-like member 74B Coil 74C Core 75 Moving apparatus 732 Conveying electrode AS Current sensor C1 Outer core part C2 Inner core part C3 Permanent magnet part T Toner TF Upper surface TT Toner extraction part

Claims (9)

An image carrier for carrying a developer image;
A developer case containing a developer and having a supply port that opens at a position facing the image carrier;
A developer transport body that includes a plurality of transport electrodes, and forms a traveling-wave electric field with these transport electrodes, thereby transporting the developer contained in the developer case toward the image carrier;
A vibrating body for vibrating the developer transport body;
An image comprising: a vibration area moving means for moving a vibration area vibrated by the vibration body along the developer transport body according to the amount of the developer in the developer case. Forming equipment. The vibration area moving means includes:
A moving device for moving the vibrating body along the developer transport body;
A control device that moves the vibrating body to a position corresponding to the upper surface of the developer in the developer transport body by controlling the moving device according to the amount of the developer in the developer case. The image forming apparatus according to claim 1. A plurality of the vibrators are arranged along the developer transport body,
The vibration area moving means includes:
A vibrator at a position corresponding to the upper surface of the developer in the developer transport body by selectively outputting a signal to the plurality of vibrators according to the amount of developer in the developer case. The image forming apparatus according to claim 1, wherein the image forming apparatus is a control device that vibrates the motor.   The image forming apparatus according to claim 2, wherein the control device performs control based on a signal from a detection unit that detects a top surface position of the developer in the developer case. The vibrator is
A permanent magnet and a coil that generates a magnetic force when energized, and configured to vibrate the permanent magnet or the coil by energizing the coil;
The detection means includes
The image forming apparatus according to claim 4, comprising: the coil; and a current sensor that detects a current flowing through the coil or a voltage sensor that detects a voltage applied to the coil.   3. The vibration suppression unit is provided on the front side and the rear side in the movement direction of the vibration body, and provided with a vibration suppression unit that contacts the developer conveyance body and suppresses vibration of the developer conveyance body. Image forming apparatus.   The image forming apparatus according to claim 1, wherein the developer transport body constitutes a part of a wall of the developer case. In a developer transport device for supplying a charged developer to a predetermined supply target,
A developer case containing the developer and having a supply port that opens at a position facing the supply target;
A developer transport body that includes a plurality of transport electrodes, and forms a traveling wave electric field with these transport electrodes, thereby transporting the developer contained in the developer case toward the supply target;
A vibrating body for vibrating the developer transport body;
And a moving device that moves the vibrating body along the developer conveying body. In a developer transport device for supplying a charged developer to a predetermined supply target,
A developer case containing the developer and having a supply port that opens at a position facing the supply target;
A developer transport body that includes a plurality of transport electrodes, and forms a traveling wave electric field with these transport electrodes, thereby transporting the developer contained in the developer case toward the supply target;
A developer conveying apparatus comprising: a plurality of vibrating bodies arranged to vibrate the developer conveying body and arranged along the developer conveying body.

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